Solid line = floor (spellings that unambiguously belong to the group). Shaded band up to the dashed edge = ceiling (the most it could reach if every ambiguous spelling counted here).
Alexandra is now well below its former popularity. All-time it's been given to 254,976 U.S. babies, the 496th most common name by sound today, peaking at 11,202 in 1993, with 1,328 in 2025.
By sound, Alexandra also includes the spellings Alexandrea.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).